Don't have
your own Little Shop of Physics Pulfrich Glasses?
You can make your own!
Step
one: Take a pair
of cheap, old sunglasses that no one wants anymore
and punch out one lens (ask an adult to help you with this part!).
Step Two:
Put them on as usual and enjoy the animations!
Or click here
to get a pair from us!
What is this "Pulfrich" you speak
of?
Pulfrich
glasses have one clear and one dark lens - this gives each of your eyes
a
different picture. The eye behind the dark lens percieves the
image later than the eye behind the clear lens. As an object
(like the swings, Earth, or pendulum) moves across the screen your
brain melds these two images together you get the illusion of depth.
This 3-dimensional effect has
been known for years
and was one of the first technologies for 3D movies!
What does this
have to do
with time?
As you know, the Little Shop of Physics has a theme for each year's
tour. The 2010 - 2011 school year's theme? It's about time!
The Pulfrich illusion only occurs because of the time delay
between your two eyes which makes it a perfect starting experiment for
this year's theme as well as the topic for another great episode
of EveryDay
Science!
Want more
EveryDay
Science?
Check out our podcast
page!
